Some of the objectives of an obstetric ultrasound examination are to determine whether the growth of a fetus is consistent with a best estimate of the fetus' age and to determine whether the relative sizes of various anatomical components are in correct proportion. To support these objectives, medical diagnostic ultrasound imaging systems can display fetal growth data in the form of “growth curves,” which depict the expected size of a component of fetal anatomy as a function of gestational age. FIG. 7 is an example of a conventional fetal growth curve showing biparietal diameter (BPD) as a function of gestational age (GA) over the course of a gestation. As shown in FIG. 7, the growth curve comprises three distinct plotted curves: one representing the mean or expected biparietal diameter for a given gestational age (curve 1), and two other curves above and below the mean showing the normal statistical variation to be found among healthy fetuses (curves 2 and 3). The growth curve also shows a data point (X), which is the biparietal diameter measurement acquired during an ultrasound examination of a patient. A sonographer or physician makes a determination regarding the status of the fetus by looking at the growth curve to determine whether the measured anatomy lies within a normal range.
Separate growth curves are generated for different types (or “dimensions”) of fetal growth data, and each of these growth curves are examined to obtain a global picture of the normalcy of the fetus' growth. Because growth curves only show a single dimension of fetal growth data and current ultrasound systems and image review systems only display a single growth curve at any given time, a sonographer or physician must page through a sequence of growth curves to diagnose the fetus', growth. This sequential analysis of growth curves introduces a risk of a missed diagnosis since a key growth curve can easily be overlooked. Similar problems can occur with other measurements of features associated with a medical image.